Automatic heat control system



June 13, 1950 G. STRYSKO 2,511,022

AUTOMATIC HEAT CONTROL SYSTEM Filed March 14, 1946 Inventor Geoiye Sizyska WWW Em Patented June 13, 1950 UNITED STATES PATENT OFFICE AUTOMATIC HEAT CONTROL SYSTEM George Strysko, Flushing, N. Y.

Application Mai-ch14, 1946, Serial No. 654,351

4 Ciaims. 1

This invention relates tosystems for controlling the. operation of heating installations in apartment houses, business and ofiiee buildings and other places with alarge number ofradiators adapted to be operated centrally in accordance with a master control, regulating their output and itv has for its object to provide a completely automatic. control of the heat supply for instance of the boiler furnishing the steam for the heating system, which is simple and efficient and which will permitto fulfill the complex requirements with a minimum of equipment,

A further object of the invention consists in providing a simple arrangement by means of which all the thermostatic and time control units will be able to influence the source of the heat supply directly and. automatically.

Further objects of the invention will be explained in the. detailed specification.

Theinvention is illustrated in the accompanying drawings with reference to one modification only. It is, however, to be understood that the fact that merely one modification of the invention. is described and illustrated isnot to be regarded as limitative.. 'I he-invention'ma-i-nlycon=- sists in thesystem used and thissystem is described in such terms that further modifications of the system and of its components and details are foreshadowed or suggested to the expert skilled in. the art, which, when included in the annexed claims, are to be considered as a part of the invention and not as a departure therefrom..

In the accompanying drawing:

Figure. 1 is a diagrammatic view of the entire heating system, showing a boiler, furnishing steam for the radiators of an apartment house or other installation, and those controls which are not connected with the proper functioning of. the boiler itself, but introduce a regulation dependent. on the outside temperature, the temperature of a standard or control room within the house, the hour of the day and similar variable outside influences.

Figure 2 is a side view'of a detail.

The diagrammatic view shown in the drawing illustrates the heating system of a building with many radiators, which may be individually adjustable or not and which may be subjected to several types of. regulations.

According to the invention a boiler 3 is provided whose fuel supply and/or pressure is regulated by suitable means and which produces and supplies the steam required for the heating of the radiators of the system.

The: boiler is. connected with the. customary limit control. switches. 8, 9: for. controlling. the pressure and: thehotwater temperature, respectively. These. limit controlv switches. contain as a; rule,.trip -switches provided With a; mercury con.- tact. The pressure control switchoperatedby a: manometric device, controls. the circuit of the motor supplying. the.v fuel. Thehot water limit control switch. controls the. hot water tempera- I tureof the.boiler.. By meansv of these switches the temperature at the water and the pressure of the steam. are automatically held at the required or desirable values.

The. regulation of the boiler 3- in accordancewith the outside temperature. and inaccordancewith: the varying. requirements. at diiierent hours of the. day andanighti is obtainedby means of. the arrangement designatedin general by the refer.- ence: letter A.. This. arrangement. consists: of. a clock Id. (Figure 2') driving ashaft. ll, carrying.

a number of camdiscslZ, [3, l4, l5. The shaft and the. cam. discs. will. rotate once within. 24 hours. The number: of cam discs isarbitrary. and depends .on the. number of different heating: periods. intowhichthe day and night is divided and whichwill require different :treatmentinaccordance with the outside-temperature;

The-discswhich are mounted on the'same shaft are shown in front View. one beside the other. in the. diagram (Figurel): for thesake of clearness. Thedisc l5,.for. example,.shows.a cam which will differentiate: between the hours of. the .day when heat; has to be provided and the hours of the night,x.sav betweenll P- M. and 5 A. M., when either the. steam supply. is cut. off or. when this supply is kept to thelowestminimum; The disc I4 is providedwitha' cam surface active during a shorter period say during the hours between 6 and- 10 A. M. and.P;.M.,when-.heat supply; is'required in the event of a higher outside temperature. Discs I3 and I2 are provided with still: smaller cam surfaces for heat supply during a few hours only.

Each cam disc 12, l3,, l4, lioperatesamovable contact arm [6, l1, l8 and l9,.respective1y, which in its turn cooperates with a fixed contact 28, 2!, 22, and 23, respectively,

The selection of the length of the periodduring which heat has to be furnished to the radiators manifestly depends onthe outside temperature, asit is, for instance, unnecessary to furnish heat during certain hours of the'night or day when the outside temperature is high. The circuits controlle'dby the cam discs I2, l3, and l5-are,

therefore, cooperating with a contact bank 28.

comprising a number of isolated segments 29. On these segments a contactor arm 39 is sliding which is driven by means of a gear 3|, illustrated diagrammatically, from a thermostat 32 shown as a bellows which is influenced by the outside air. The contact arm 39 will, therefore, be moved to one of the segments 29 in accordance with the outside temperature and all those segments 29 which are to be active at this temperature may be interconnected and connected with the conductors 24, 25, 26 and 21, respectively, leading to the cam operated contacts 29, 2|, 22, 23, respectively, which regulate the heat required for the particular period of the day.

For instance, up to a certain temperature say 35 or 40 the cam disc |5 will close the control circuit at contacts I9 and 23 during all day hours. The segments up to this temperature are interconnected at 33 and if the contact arm 39 rests on one of these segments the circuit containing these contacts (I9, 23) and conductor 21 will be completed by the branch conductor 34 leading to the contact arm 39. If the temperature is higher, say 50, the contact arm 39 will rest on a segment corresponding to this position and the circuit through contacts I9, 23 is cut out. However, the circuit of cam disc 14 is now connected, which is closed only during a much shorter period in the morning and evening hours in accordance with the higher atmospheric temperature. Still higher atmospheric temperatures require shorter and shorter periods of boiler activity as will be seen from the cam surfaces of discs l2 and I3 connected with the segments 29 reached only at higher outside temperatures.

In addition to the selection as above explained, a thermostatic control may be provided to maintain a predeterminedtemperature. This is performed by the apparatus, generally referred to by the letter B which consists of a regulation thermostat 35 arranged in a regulation room temperature of which may be considered to be at the desirable or regulation value, which room is preferably located at a central spot. In an apartment house or hotel this room may be the lobby, hall or vestibule or any other similar room. The regulation thermostat has, of course, to be mounted at a place which is not subject to draft or to sudden temperature changes. This thermostat is adjusted to the temperature which should be upheld in the system. The thermostat contacts are connected with the branch conductor 34 leading to the contactor arm 39 of apparatus A and with the conductor 36 which leads to the line transformer 31 from which the control system is supplied with current.

The control system comprises the two relays 39 and 49, each of which is provided with a number of relay contacts. In the example shown starting relay 39 is provided with two pairs of contacts 4|, 42 of which contact 4| controls a circuit 48 shunting the limit switch 9 while contact 42 closes the circuit of boiler control relay 49 which is provided with two contact pairs 45, 46. The latter contact is merely a holding contact keeping its own winding energized. The former keeps the circuit 48 closed, upon energization of the relay 49. A normally open manual switch 6| may be provided in a branch which is parallel to the limit control 9 which permits to short circuit said control.

The energizing circuit 49, 59 of the relay 49, as seen, includes the motor 5| of the oil burner or stoker which supplies the fuel and which is connected with said circuit at the temminals 5, 6.

It is to be understood that the boiler and relay arrangement may be provided with all the other equipment which is usually or in certain cases part of such an installation. Thus, for instance, in the case of an intermittent oil burner the well known apparatus for the control of intermittent ignition is inserted, to secure regular function of the intermittent burner. The motor 5| of the boiler fuel supply is sometimes operated by a magnetic switch, which has to be connected to the circuit 5, 6 instead of the motor circuit, while the latter is a separate circuit operated by the magnetic switch. These and other modifications are obvious to those skilled in this art and are mere adaptations of the system to given or prescribed conditions.

The operation of the arrangement is the following.

Assuming first that the water in the boiler has reached a certain low temperature then the limit control switch 9 will be tripped and will operate the boiler motor, in order to heat the water. The latter operation is performed, by closing a circuit starting at the line terminals 3, 4 and running from 3 over line 53 closed switch 9 and over closed pressure control switch 8 to terminal 6 and from here to motor 5|, terminal 5 and line terminal 4.

This operation as seen does not affect the heat control in any way. It is, therefore, performed in the same way in which it is performed in known installations. When the water in the boiler has been heated, the circuit is broken by limit control switch 9 and the boiler motor ceases to operate.

Assuming now that the heat control operates and calls for a heating of the system and further assuming that the outside temperature 32 is 39", then the thermostat will move the contactor arm 39 to a contact segment 29 corresponding to this temperature. This segment is connected with conductor 21 and the cam contact arm l9. When the cam |5 therefore closes contacts I9 and 23 a circuit will be closed which runs from one end of the secondary of the line transformer 31, over conductor 56 to contacts 23, contact arm |9, con ductor 21, segment 29, arm 39, line 34, closed thermostat 35, line 36, relay winding 39 to the other end of the secondary winding of transformer 37. It will be noted that when the system is heated insufliciently, the regulation thermostat 35 is closed, and that the relay will therefore operate. This relay cuts out the limit control switch 9 by providing a shunt around it as the circuit 48 is closed at contacts 4| of relay 39.

The relay contacts 42 close the energizing circuit of relay 49, and operate the motor 5| supplying fuel. The circuit for relay 49 starts at line terminal 3 and runs over conductor 53, circuit 48, now closed at contacts 4|, conductor 54, closed pressure control switch 8, to point 69, conductor 59, closed contacts 42, relay winding 49 and to line terminal 4.

Simultaneously, the energizing circuit of the motor 5| is closed, the circuit branching off from point 69 and running over terminals 6 and 5 back to line terminal 4.

It will be noted that when relay 49 operates it closes contacts 45 and 46 which are arranged in parallel to contacts 4| and 42 in the circuits 48 and 49, 59.

The boiler now operates and supplies the system with heat until the re ulation thermostat 35 opens upbecause theregulation room inwhich itis located hasreached the-normal temperature. This does notmean however, that the entiresystem has reached this temperature. lhe regulation thermostat therefore, cuts out relay 39 by opening its energizing circuit (as above described) but the boiler does not cease to operate as relay 40 is still energized until the boiler reaches thesteam pressure to which it has been set. When this limit has been reached, it is certain that the entire system is at least at the temperature of the standard room.

The pressure switch then cuts off the connection through conductor 54 and relay 4% falls back and the motor- 5| iscut out.

It 'willthus be-seenthat the system is under the control of a plurality of controlling elements which influence the heating medium supplied, but once operated, is not cut out until the prescribed pressure hasbeen reached. The pressure control switch is of course, merely an example. If the system operates with hot water the temperature of the water may be the controlling influence. The main point is that the system operates until a pre-set condition of heating is reached in the system, even after the controls initiating the heating or set to control excessive heating have fallen back. This. is necessary in a complex heating system because there is no point in the system which, when regulated, will be able to indicate that, in fact, all points of the system havereached' the desired conditions. These conditions have therefore, to be set at a central point or at. the source of'heat supply.

' It will thusbe seen that a simple and efiective completely automatic control of the heating system can take place as the boiler is under control of the combined influence of the pressure control switch, of the thermostat in the regulation room, of the thermostat and switch influenced by the outside temperature and of the timing arrangement which sets the periods of heatin in accordance with the hours of the day.

It will be manifest that many changes of the details of the system are possible without departing from the essence of the invention.

I claim:

1. An electric control system for heating systems, provided with a boiler having electrically driven boiler heat control means, controlled by a minimum limit control switch, responsive to the temperature of the water and operating said heat control means when said temperature drops below a predetermined limit and by a maximum limit control switch, responsive to a predetermined boiler pressure and cutting off said heat control means when the pressure exceeds a predetermined value, said electric control system comprising a boiler control relay system for controlling the operation of the electrically driven heat control means, independently of the minimum limit control switch and in conjunction with the maximum limit control switch, an energizing and a holding circuit for the relay system, the latter controlled by said maximum limit control switch, responsive to the boiler pressure, a regulation thermostat responsive to a predetermined temperature in a regulation room, having contacts arranged within the energizing circuit of the relay system, a plurality of clock operated means, each limiting the time during which the energizing circuit is kept closed in readiness for operation to a predetermined period of a day, and a thermostatically operated selector mechanism, responsive to the prevailing outside air temperature for. selecting oneof said clock operated means-,said relay system being thus: 61181?! gized'. overthea clock operated. means, selected bythe. temperature. responsive selector mechanism,

and; over the contacts of the regulation thermostat, andde-energizedbythe maximum limit contI'Oli boiler pressure responsive. switch.

2 An electric control system for heating systems. provided: with a. boiler, having, an electrically driven boilerv heat control means, controlled by aminimum limit control. switch, responsive tothe temperature of: the water and, operating said, heat. control. means. when said temperature drops.- below. a predetermined limit and by a maximum.

limit. control switch, responsive to a predetermined boiler pressure, and cutting oiT said heat.

control means when the pressure exceeds a predetermined" value,- saicl; electric control system omprising an energizin circuit for said heat control means, a, boiler controlrelay system for controllingthe operationof theelectrically driven heat control meanaindependently of the mini-.

mum limit controlv switch andin. conjunction with the maximum. limit, control, switch, an energizing and a holding circuit for-the relay system, the latter controlled by said maximum limit switch, re-- sponsive, to, thelboiler pressure, a regulation thermostat responsive, to a. predetermined temperar fin; a r gulation: room, having contacts ar ranged within the energizing circuit, of the relay system, a plurality of clock operated means, each limiting the time during, which the, energizing circuit. is keptclosed in readiness for operation to a. predetermined period of: a.day,.and a thermostatically operated selector mechanism, respon' sive to the prevailing outside air temperature for selecting one of said clock operating means;

means for, supplying. said circuits with current, sa1d relay system being energized from said cur-- rent supply means over the clock operated means and over the contacts of the regulation thermostat, and means operated by said relay system for shifting the energizing conection from the above named energizing circuit to the hOldlIlg circuit controlled by the maximum limit pressure responsive switch, said relay system and boiler heat control means being thus energized over the clock operated means and regulation thermostat and de-energized by the maximum limit control pressure responsive switch.

3. An electric control system for heating systems provided with a boiler having electrically driven boiler heat control means, controlled by a minimum limit control switch, responsive to the temperature of the water and operating said heat control means, when said temperature drops below a predetermined limit and by a maximum limit control switch, responsive to a predetermined boiler pressure and cutting off said heat control means when the pressure exceeds a predetermined value, said electric control system comprising an energizing circuit for said heat control means, a boiler control relay system, including interdependent relays, one of said relays being a starting relay initiating the operation of the heat control means and controlling the energizing circuit of the same, a second relay being a holding relay, holding the above mentioned energizing circuit of the heat control means closed, an energizing circuit for said starting relay and an energizing circuit for said holding relay, the latter circuit being closed by said starting relay and being controlled by the said maximum limit control switch, responsive to the boiler pressure, a regulation thermostat, responsive to a predetermined temperature in a regulation room, having contacts arranged within the energizing circuit of the starting relay, a plurality of clock operated means controlling the latter circuit, each limiting the time during which the energizing circuit of the starting relay is kept closed and in readiness for operation to a predetermined period of a day, and a thermostatically operated selector mechanism, responsive to the prevailing outside air temperature for selecting one of said clock operated means, said relay system being energized over the clock operated means, selected by the temperature responsive selector mechanism, and over the contacts of the regulation thermostat, while being de-energized by the maximum limit control switch responsive to the boiler pressure.

4. An electric control system for heating systems, provided with a boiler having electrically driven boiler heat control means, controlled by a minimum limit control switch, responsive to the temperature of the water and operating said heat control means when said temperature drops below a predetermined limit and by a maximum limit control switch, responsive to a predetermined boiler pressure and cutting off said heat control means when the pressure exceeds a predetermined value, said electric control system comprising an energizing circuit for said heat control means, a boiler control relay system, including a starting relay, an energizing circuit for the same, contact means operated by said starting relay for cotrolling the energizing circuit of said heat control means, a holding relay, an energizing circuit for the same, the said energizing circuit being controlled by contact means operated by said starting relay and by the maximum limit control switch, said holding relay closing an energizing circuit of the heat control means and its own energizing circuit and holding said circuits closed irrespective of the position of the starting relay, a regulation thermostat, responsive to a predetermined temperature in a regulation room, having contacts arranged in the energizing circuit of the starting relay, a plurality of arcuate earns, a shaft carrying the same, a clock mechanism operating said shaft, contact sets closed by said cams, each of said cams having an arcuate length keeping its contact set closed during a predetermined period of a day, a set of fixed contacts, each of them connected with one of the cam operated contact sets, a contact selector arm, moving over said fixed contacts, a selector thermostat, responsive to the temperature of the outside air, and connected with the selector contact arm, moving the same over the fixed contacts, said selector arm being connected electrically with the regulation thermostat, said cam operated contacts, fixed contacts, selector contact arm, and contacts of the regulation thermostat all controlling the energizing circuit of the starting relay of the boiler control relay system.

GEORGE STRYSKO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,604,342 Greenhut Oct. 26, 1926 1,694,323 Jump Dec. 4, 1928 1,925,455 Morgan Sept. 5, 1933 2,062,337 Stewart Dec. 1, 1936 2,192,859 Scoggin Mar. 5, 1940 2,275,427 Greenlee Mar. 10, 1942 2,323,411 Newman July 6, 1943 

